Baking is exact amounts, humidity percentages, controlled environments

Yes but no. Humidity and environment will change how the bread turns out, but even in large industrial bakeries where they chemically analyse the flour and have influence over microbiomes they know that the slightest, uncontrollable, variation can throw things off so you still have people listening to how the dough sounds in the kneader, how sproingy it is after proofing, and make calls about whether the dough needs some more or less work or time.

It might be possible to fully automate things by killing the flour (by default it contains lots of microorganisms), use yeast only (while you can get pure-strain sourdough it’s still a more fickle beast than straight yeast), but then you probably need to be American to still call the final product bread.

By contrast if you’re a baker’s apprentice in Germany for the first year you’ll be forbidden to touch the kneader, you need to have heard lots of doughs and observed many a decision the master makes on the fly about what exactly to do to the dough and why until you have the necessary intuition to start making calls on your own. The first thing you learn is dough tension and how to knead two loaves at the same time, messing up there is not a biggie you just gotta have to start over. Not exactly German but here’s a good video about dough tension. It’s important for every elastic dough and baguettes are particularly finicky so it’s a good example.

I think the reason you hear the “baking is a science” trope: People can’t actually bake. Sure, using exact amounts will get you a better result if you don’t know anything about dough but once you do you’ll be adjusting things on the fly to account for things like initial water content in the flour and the phase of the moon. Baking is alchemy.